Single-cylinder internal heating type heat engine

Abstract

The invention relates to a single-cylinder internal heating type thermomotor, which comprises a cylinder body assembly, which comprises a hot-end cylinder body and a cold-end cylinder body, the hot-end cylinder body and the cold-end cylinder body are combined and butted to form a closed single cylinder body, and a heat insulation ring is arranged between the hot-end cylinder body and the cold-end cylinder body; the first heat exchanger is arranged in the hot end cylinder body, is in fluid communication with an external heat source and is used for heating working gas in the hot end cylinder body; the second heat exchanger is arranged in the cold-end cylinder body, is in fluid communication with an external cold source and is used for cooling working gas in the cold-end cylinder body; the piston is installed in the cylinder body assembly, the piston is provided with an air flow channel and an air valve, the air flow channel is used for communicating working air in the hot end cylinder body with working air in the cold end cylinder body, and the air valve is used for controlling on-off of the air flow channel; one end of the piston rod is fixed to the piston, and the other end of the piston rod is connected with a transmission mechanism located outside the cylinder body. The air cylinder of the thermomotor is simple in structure, resistant to high pressure and higher in thermal power.

Description

Single-cylinder internal heat hot gas engine

[0001] Cross-application

[0002] This application claims priority to the Chinese invention patent application number 202410242995.6 filed on March 4, 2024, entitled “A New Single-Cylinder Stirling Engine,” the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present invention belongs to the field of engines, and in particular relates to a single-cylinder internal heat type hot gas engine. Background Art

[0004] The working principle of the steam generator is as follows:

[0005] The two cylinder-piston systems consist of a hot-end cylinder and a cold-end cylinder. The working fluid in each cylinder is connected via a heat accumulator channel. Driven by the flywheel, the gas in the cold-end cylinder is compressed. Heat is dissipated through the cylinder walls, causing the cold-end gas to contract and enter the hot-end cylinder through the heat accumulator. The hot-end cylinder, heated by an external heat source, expands, performing external work and pushing the piston in the hot-end cylinder. This piston movement rotates the connecting rod and crankshaft, outputting power. After the hot-end piston reaches a stop, it returns to its original position driven by the flywheel, compressing the gas in the cylinder and transferring it to the cold-end cylinder. The gas loses heat in the cold-end cylinder, contracting in volume. The piston returns to its original position, forcing the gas through the heat accumulator and into the hot-end cylinder for circulation.

[0006] Due to the material and strength design of the cylinder, the heat transfer coefficient of the hot gas engine is low, resulting in slow heat transfer to the external heating and low engine power. The cylinder-crankcase structure makes it difficult to install and arrange in the workplace.

[0007] Summary of the Invention

[0008] The object of the present invention is to provide a single-cylinder internal heat type hot gas engine to solve the above problems. To this end, the technical solution adopted by the present invention is as follows:

[0009] A single-cylinder internal heat type hot gas engine may include:

[0010] Cylinder assembly, the cylinder assembly comprising a hot end cylinder and a cold end cylinder, the hot end cylinder and the cold end cylinder are combined and docked to form a closed single cylinder and an insulation ring is provided between them;

[0011] a first heat exchanger installed in the hot end cylinder and in fluid communication with an external heat source for heating the working gas in the hot end cylinder;

[0012] a second heat exchanger installed in the cold-end cylinder and in fluid communication with an external cold source for cooling the working gas in the cold-end cylinder;

[0013] A piston, wherein the piston is a single piston, installed in the cylinder assembly and capable of reciprocating linear motion in the cylinder assembly, wherein the piston is provided with an air flow channel and a valve, wherein the air flow channel is used to connect the working gas in the hot end cylinder and the cold end cylinder, and the valve is used to control the on / off of the air flow channel; and

[0014] A piston rod, one end of which is connected to the piston, and the other end of which is connected to a transmission mechanism located outside the cylinder assembly.

[0015] In one embodiment, the valve includes a valve gate and a valve driving mechanism, the valve gate is provided with a through hole, and the piston is provided with an axial air vent as the air flow channel; the valve gate and the valve driving mechanism are installed on the piston; the valve driving mechanism is used to drive the valve gate to rotate so that the through hole of the valve gate and the axial air vent of the piston are aligned or staggered, that is, to achieve the opening or closing of the valve.

[0016] In one embodiment, the valve drive mechanism includes a control rack, a control gear and a pneumatic device, wherein the control gear and the valve gate are coaxially fixedly mounted on a sleeve, and the sleeve is rotatably mounted on the piston rod; the pneumatic device is mounted on the piston and connected to the control rack; the control rack is engaged with the control gear to drive the control gear to rotate.

[0017] In one embodiment, the valve damper is in the shape of a disc.

[0018] In one embodiment, the axial ventilation hole includes two radially symmetrical circular through holes.

[0019] In one embodiment, the external heat source includes a heating device and a first circulation pump, and the first heat exchanger, the first circulation pump and the heating device are connected through corresponding pipes to form a heat medium circulation loop.

[0020] In one embodiment, the external cold source includes a refrigeration device and a second circulation pump, and the second heat exchanger, the second circulation pump and the refrigeration device are connected through corresponding pipelines to form a cold medium circulation loop.

[0021] In one embodiment, a through hole is provided at one end of the cylinder assembly for the piston rod to pass through, and the through hole cooperates with the piston rod to seal the working gas in the cylinder assembly.

[0022] In one embodiment, the through hole is provided at the end of the cold end cylinder.

[0023] In one embodiment, the transmission mechanism includes a transmission gear and a transmission rack, the transmission rack is fixedly connected to the piston rod, and the transmission gear is meshed with the rack.

[0024] The present invention adopts the above solution, which has the beneficial effects of:

[0025] The present invention provides a new design in which cylinder hot and cold end heat exchangers serve as heat and cold sources, placed inside the cylinder to directly heat and cool the working gas within the cylinder. Compared to the Alpha-type Stirling engine, an external heat source directly heats the cylinder block. Due to the greater structural strength and low thermal conductivity of the cylinder block, this affects the engine's thermal power. Compared to the Beta-type Stirling engine, an external heat source directly heats the pipes connected to the cylinder. However, due to the lower strength of high-thermal-conductivity metal materials such as pipes at high temperatures, this becomes a shortcoming in the cylinder's strength and limits the maximum pressure of the gaseous working medium within the cylinder. In this design, the hot-end heat exchanger and the cold-end heat exchanger can withstand extremely high external working gas pressures, resulting in a simple cylinder structure, higher thermal power, and better pressure resistance.

[0026] Since both the hot medium and the cold medium are transported to the inside of the cylinder through pipes, the engine can be arranged away from the heat source and the cold source, which greatly facilitates the installation and use of the equipment and greatly expands the application scenarios of this design scheme.

[0027] The single piston, transmission shaft, and rack-and-pinion mechanism replace the crankshaft-connecting rod-flywheel mechanism of the traditional Stirling engine, effectively simplifying the engine structure, reducing mechanical losses, improving mechanical efficiency, and greatly reducing installation space and equipment weight. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] FIG1 is a schematic diagram of a single-cylinder internal heat type hot gas engine according to an embodiment of the present invention;

[0029] FIG2 is a schematic diagram of a piston and valve of a single-cylinder internal heat hot gas engine according to an embodiment of the present invention;

[0030] FIG3 is a schematic diagram of the working principle of the pneumatic device of the valve shown in FIG2 .

[0031] Figure markings: 1-cylinder assembly; 11-hot end cylinder; 12-cold end cylinder; 13-insulating ring; 14-through hole; 2-first heat exchanger; 21-heating equipment; 22-first circulating pump; 23-delivery pipeline; 3-second heat exchanger; 31-refrigeration equipment; 32-second circulating pump; 4-piston; 41-axial vent; 6-valve; 61-valve gate; 611-through hole; 62-valve control mechanism: 620-pneumatic device; 623-energy storage cylinder; 624-pressure control valve; 625-actuator cylinder; 626-one-way intake valve; 621-control rack; 622-control gear; 63-sleeve; 5-piston rod; 81-transmission gear; 82-transmission rack; P1-hot stop point; P2-cold stop point. DETAILED DESCRIPTION

[0032] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings so that the objects, features and advantages of the present invention can be more clearly understood. It should be understood that the embodiments shown in the accompanying drawings are not intended to limit the scope of the present invention, but are only intended to illustrate the essential spirit of the technical solution of the present invention.

[0033] In the following description, for the purpose of illustrating the various disclosed embodiments, certain specific details are set forth in order to provide a thorough understanding of the various disclosed embodiments. However, those skilled in the relevant art will recognize that the embodiments may be practiced without one or more of these specific details. In other cases, well-known devices, structures, and techniques associated with this application may not be shown or described in detail to avoid unnecessarily obscuring the description of the embodiments.

[0034] Unless the context requires otherwise, throughout the specification and claims, the word "comprise" and variations such as "include" and "have" should be construed in an open, inclusive sense, that is, should be interpreted to mean "including, but not limited to."

[0035] Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any manner in one or more embodiments.

[0036] As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. It should be noted that the term "or" is generally employed in its sense including "and / or" unless the context clearly dictates otherwise.

[0037] In the following description, in order to clearly demonstrate the structure and working mode of the present invention, many directional words will be used for description, but words such as "front", "back", "left", "right", "outside", "inside", "outward", "inward", "up", and "down" should be understood as convenient terms and should not be understood as restrictive terms.

[0038] Furthermore, terms such as "horizontal," "vertical," and "overhanging" do not necessarily imply that a component must be absolutely horizontal or overhanging, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but rather that it can be slightly tilted.

[0039] It should also be noted that, in the description of this application, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0040] As shown in Figure 1, a single-cylinder internal heat engine may include a cylinder assembly 1, a first heat exchanger 2, a second heat exchanger 3, a piston 4, and a piston rod 5. The cylinder assembly 1 is a sealed single-cylinder structure. It can be divided into a hot-end cylinder 11 and a cold-end cylinder 12. The hot-end cylinder 11 and the cold-end cylinder 12 are joined together to form a sealed single cylinder. It should be understood that the cylinder assembly may also be provided with removable end caps at one or both ends to facilitate installation and maintenance of components within the cylinder. A thermal insulation ring 13 may be used to insulate the hot-end cylinder 11 and the cold-end cylinder 12 to prevent heat conduction between them.

[0041] The first heat exchanger 2, also known as the hot-end heat exchanger, is installed within the hot-end cylinder 11, located at the end of the hot-end cylinder 11 of the cylinder assembly 1, and is fluidly connected to an external heat source for heating the working gas within the hot-end cylinder 11. The second heat exchanger 3, also known as the cold-end heat exchanger, is installed within the cold-end cylinder 12, located at the end of the cold-end cylinder 12 of the cylinder assembly 1, and is fluidly connected to an external cold source for cooling the working gas within the cold-end cylinder 12. The first heat exchanger 2 and the second heat exchanger 3 can be made of a metal material with high thermal conductivity. For example, the first heat exchanger 2 and the second heat exchanger 3 can be made of copper. The first heat exchanger 2 and the second heat exchanger 3 are located outside the travel of the piston 4.

[0042] Piston 4 is a single piston, mounted within cylinder assembly 1 and capable of reciprocating linear motion within cylinder 1, namely, between hot and cold dead points P1 and P2. Piston 4 is equipped with a valve and an airflow passage extending through the cylindrical piston 4. The airflow passage connects the working gas within the hot-end cylinder 11 and the cold-end cylinder. Valve 6 controls the flow of the airflow passage, i.e., the flow of working gas between the hot-end cylinder 11 and the cold-end cylinder 12. Specifically, at the end of the temperature increase and expansion of the working gas in the hot-end cylinder 11, the valve 6 opens, and the high-temperature and high-pressure working gas enters the cold-end cylinder 12 from the hot-end cylinder 11 through the air flow channel, and then the valve closes, and the piston 4 moves toward the cold end of the cylinder assembly 1, further compressing the working gas in the cold-end cylinder 12; similarly, at the end of the expansion of the working gas in the cold-end cylinder 12, the valve 6 opens, and the working gas enters the hot-end cylinder 12 from the cold-end cylinder 11 through the air flow channel, and then the valve 6 closes, and the piston 4 moves toward the hot end, compressing the working gas in the hot-end cylinder 11.

[0043] One end of the piston rod 5 is connected to the piston 4, and the other end is connected to the transmission mechanism 8 located outside the cylinder assembly 1, so that the reciprocating motion of the piston 4 is output as power through the transmission mechanism 8. Specifically, a through hole 14 is provided at the axis of one end (for example, the cold end) of the cylinder assembly 1, and the piston rod 5 passes through the through hole 14 and is connected to the transmission rack 82 of the transmission mechanism 8. The through hole 14 of the cylinder assembly 1 cooperates with the piston rod 5 to seal the high-pressure working gas in the cylinder. In this embodiment, the transmission mechanism 8 includes a transmission gear 81 and a transmission rack 82. The transmission rack 82 is fixedly connected to the piston rod 5, and the transmission gear 81 is engaged with the transmission rack 82. The transmission gear 81 outputs power to user equipment such as a generator by rotation. When the piston 4 reciprocates in a straight line, it drives the transmission gear 81 to rotate to achieve power output.

[0044] In the single-cylinder internal heat engine of this application, the first and second heat exchangers 2 and 3 are located within the cylinder and are not part of the cylinder. They serve as heat and cooling sources, directly heating and cooling the working gas within the cylinder. The pipes connecting the first and second heat exchangers 2 and 3 to the exterior of the cylinder assembly 1 contain a liquid medium that can withstand the extreme pressures of the cylinder working gas. This results in a simple cylinder structure, higher thermal efficiency, and improved pressure resistance.

[0045] The external heat source includes a heating device 21 and a first circulation pump 22. The heating device 21, first circulation pump 22, and first heat exchanger 2 are connected in sequence by a pipeline 23 to form a heat medium circulation loop. The heating device 21 heats the liquid medium outside the cylinder, away from the cylinder. The first circulation pump 22 then transports the heat via a pipeline to the first heat exchanger 2 located within the hot-end cylinder body 11. The first heat exchanger 2 acts as a heat source, directly heating the high-pressure working gas within the cylinder. This expands the working gas, pushing the piston 4 to produce work. After the liquid medium loses heat in the first heat exchanger 2, it is transported back to the heating device 21 outside the cylinder via a pipeline for further heating. The heating device 21 can utilize solar energy, fuel, or other heating methods.

[0046] Similarly, the external cold source includes a refrigeration unit 31 and a second circulating pump 32. The refrigeration unit 31, the second circulating pump 32, and the second heat exchanger 3 are connected in sequence by pipes to form a cold medium circulation loop. The refrigeration unit 31 cools the liquid refrigerant, which is then transported via pipes by the second circulating pump 32 to the second heat exchanger 3 located within the cold-end cylinder 12. The second heat exchanger 3 acts as a cold source within the cold-end cylinder 12, directly cooling the working gas. The working gas contracts, pulling the piston 4 in a linear motion toward the cold end of the cylinder. When the piston 4 reaches the cold dead point P2, it compresses the working gas within the cold-end cylinder 12 to a high pressure. At this point, the piston 4 reverses its motion. When the working gas pressure within the cold-end cylinder 12 drops to a set value, the valve 6 opens, freeing the piston 4 to flow through the air passage, allowing the cold, high-pressure working gas within the cold-end cylinder 11 to be discharged into the hot-end cylinder 11. At the cold end, the refrigerant absorbs heat, increases in temperature, and is then transported via pipes back to the refrigeration unit 31 outside the cylinder to dissipate heat, thereby providing cooling. The structure of the refrigeration unit 31 is well known and will not be further described here.

[0047] As shown in Figures 2 and 3, in this embodiment, the valve 6 may include a valve gate 61 and a valve drive mechanism 62. The valve gate 61 is disc-shaped and is coaxially mounted within the piston 4 and rotatable relative to the piston 4. The valve gate 61 is provided with through holes 611 (two shown), and the piston 4 is provided with axial vents 41 (two shown), which serve as airflow channels between the hot-end cylinder 11 and the cold-end cylinder 12. In this embodiment, the two axial vents 41 are radially symmetrical to facilitate control. It should be understood that the number and layout of the axial vents 41 are not limited to the illustrated embodiment. The valve drive mechanism 62 is fixedly mounted on the piston 4 and is used to drive the valve gate 61 to rotate so that the through holes 611 and the axial vents 41 of the piston 4 are aligned or offset, thereby achieving the opening or closing of the valve. When the valve 6 is open (i.e., the axial air vent 41 is aligned with the through hole 611), the working gas in the hot-end cylinder 11 can enter the cold-end cylinder 12 or the working gas in the cold-end cylinder 12 can enter the hot-end cylinder 11; when the valve 6 is closed (i.e., the axial air vent 41 is staggered and not connected to the through hole 611), the working gas cannot flow between the hot-end cylinder 11 and the cold-end cylinder 12.

[0048] In this embodiment, as shown in Figure 3, the valve drive mechanism 62 includes a control rack 621, a control gear 622 and a pneumatic device 620. The control gear 622 and the valve gate 61 are coaxially mounted and fixed on a shaft sleeve 63, and the shaft sleeve 63 is rotatably mounted on the piston rod 5. One end of the control rack 621 is a rack part, and the other end is a rod; the pneumatic device 620 is fixedly connected to one end of the control rack 621 (i.e., the rod part), and the other end of the control rack 621 (i.e., the rack part) is engaged with the control gear 622. The pneumatic device 620 uses the high-pressure working gas in the cylinder assembly 1 as power to drive the control rack 621 to move, thereby driving the valve gate 61 to rotate, thereby opening and closing the air flow channel. The structure of the pneumatic device 620 is described in detail below. Figure 3 shows a schematic diagram of the working principle of the pneumatic device 620. Pneumatic device 620 includes an energy storage cylinder 623, a pressure control valve 624, and an actuator cylinder 625. These three components, including energy storage cylinder 623, pressure control valve 624, and actuator cylinder 625, all represent mature, readily designable, and implementable industrial technologies. Energy storage cylinder 623 receives high-pressure working gas from the outside world through inlet port D of one-way inlet valve 626. An interlock is provided between the inlet and outlet of the energy storage cylinder, ensuring that the outlet is closed during the inlet phase. Pressure control valve 624 is a pressure-controlled, three-way, two-way valve. Depending on the working gas pressure within the cylinder, a spring is compressed, positioning the three-way, two-way control valve core in positions A, B, or C, corresponding to the outlet of energy storage cylinder 623. Specifically, when the cylinder pressure reaches different setpoints, the spring is compressed, causing the outlet of the energy storage cylinder 623 to correspond to the three positions A, B, and C of the three-way, two-way valve.

[0049] The operating process of the pneumatic device 620 on the hot-end cylinder 11 side will now be described as an example. When the piston 4 is located in the center of the cylinder 1, the pressure within the hot-end cylinder 11 is low. The spring of the pressure control valve 624 expands, pushing the three-position, two-way valve core to the right, locating it in the rightmost position. This means that the outlet of the energy storage cylinder 623 corresponds to the inlet of the pressure control valve in position A. The spring within the actuator cylinder 625 pushes the piston within the actuator cylinder to the left of the actuator cylinder 625. The piston within the actuator cylinder 625 is fixedly connected to the control rack 621 of the valve drive mechanism, which is retracted. The valve 6 is initially closed. At this point, the control rack 621 of the valve drive mechanism on the cold-end cylinder 12 side, which is symmetrically mounted left and right, also retracts, and its three-position, two-way valve is also in the low-pressure position A. When the engine's starting motor drives piston 4 toward the hot end, the working gas in hot-end cylinder 11 is compressed and pressurized due to the closure of valve 6. The gas pressure in energy storage cylinder 623 is lower than that in the hot-end cylinder 11. High-pressure working gas outside energy storage cylinder 623 enters energy storage cylinder 623 through inlet port D of one-way inlet valve 626. At this point, the output pipeline of energy storage cylinder 623 is also closed. When piston 4 reaches hot dead point P1, the working gas pressure in hot-end cylinder 11 reaches its maximum value. While the working gas pressure in hot-end cylinder 11 increases, the output pipeline of energy storage cylinder 623 remains closed. As the working gas pressure in hot-end cylinder 11 increases, the spring of pressure control valve 624 is compressed, and the three-position, two-way valve core of pressure control valve 624 is eventually pushed to position C by pressure. This means that the outlet of energy storage cylinder 623 corresponds to the inlet port C of the pressure control valve. In this position, the two-way flow path of actuator cylinder 625 is interrupted. When piston 4 moves in the opposite direction from hot dead point P1 toward cold-end cylinder 12, the working gas pressure within hot-end cylinder 11 begins to decrease, and the outlet of energy storage cylinder 623 (the outlet switch valve is linked to the rise and fall of gas pressure) opens. When the working gas pressure within hot-end cylinder 11 drops to the set value, the gas within hot-end cylinder 11 no longer flows into cold-end cylinder 12 in large quantities, and valve 6 needs to be closed. The three-position, two-way valve core of pressure control valve 624 senses the decrease in working gas pressure within hot-end cylinder 11 and is pushed by the spring to position B, corresponding to the outlet of energy storage cylinder 623. At this point, the high-pressure gas within the energy storage cylinder flows through the passage within pressure control valve 624 and enters the left chamber of actuator cylinder 625, pushing the piston of actuator cylinder 625 to the right and compressing the spring within actuator cylinder 625. Simultaneously, the gas within the right chamber of actuator cylinder 625 is discharged through the outlet pipe corresponding to the passage of pressure control valve 624. The piston of the actuator cylinder 625 drives the control rack 621 to move, pushing the control gear 622 to rotate, thereby opening the valve 6. The high-temperature and high-pressure gas in the hot-end cylinder 11 can enter the cold-end cylinder 12 through the valve 6. At this time, the rack 621 is in the extended state.Because the hot-end vent valve and the cold-end vent valve are fixedly connected via a sleeve and rotate coaxially in this embodiment, the rotation of the hot-end valve 6 will drive the cold-end valve 6 to rotate synchronously, thereby driving the cold-end control rack 621 to its extended state. Because the cold-end cylinder 12 is at low pressure, the valve core of its pressure control valve 624 is always in position C, corresponding to the outlet of the energy storage cylinder 623. As shown in Figure 3, the valve core of the cold-end pressure control valve is in position C, connecting the chambers on both sides of the actuator cylinder 625, and the outlet of the energy storage cylinder 623 is exhausted through the passage of the pressure control valve 624. As the piston 4 continues to move toward the cold-end cylinder 12, the working gas pressure in the hot-end cylinder 11 further decreases. When it drops to the set pressure value, the working gas in the hot-end cylinder 11 no longer flows into the cold-end cylinder 12 in large quantities. The hot-end pressure control valve 624 senses the decrease in working gas pressure within the hot-end cylinder, further expanding the spring and pushing the three-position, two-way valve core to position C. This means that the high-pressure gas outlet line within the energy storage cylinder 623 corresponds to the three-position, two-way valve position C of the pressure control valve 624. The high-pressure gas from the energy storage cylinder 623 is diverted into the right chamber of the actuator cylinder 625, where it, together with the compression spring within the actuator cylinder 625, pushes the piston of the actuator cylinder 625 toward the left, thereby driving the connected control rack 621 to move and close the valve. At this point, the hot-end control rack 621 retracts, and the symmetrically mounted rack on the cold-end also retracts. The operating process of the pneumatic device 620 on the cold-end cylinder 12 is identical to that of the pneumatic device on the hot-end side and will not be further explained. It should be understood that the structure of the pneumatic device 620 is not limited to that described in this embodiment.

[0050] In one embodiment, a regenerator (not shown) may be provided in the piston 4 to improve the thermal efficiency of the engine.

[0051] The working process of the single-cylinder internal heat type heat engine of this application is described below:

[0052] S1: The high-pressure working gas in the hot-end cylinder 11 is heated and expanded by the first heat exchanger 2, increasing its pressure and temperature, pushing the piston 4 toward the cold-end cylinder 12. During this process, the heating device 21 heats the liquid medium, and the first circulation pump 22 continuously delivers the hot liquid medium to the first heat exchanger 2 to heat the working gas in the hot-end cylinder 11. The working gas in the hot-end cylinder 11 heats up and expands, pushing the piston 4 toward the cold-end cylinder 12. At the end of the expansion of the high-temperature and high-pressure working gas in the hot-end cylinder 11, as the volume of the hot-end cylinder increases, the pressure of the working gas in the cylinder decreases. When the pressure reaches the set value, the valve control mechanism 62 opens the valve 6, opening the airflow channel of the piston 4, and the high-temperature and high-pressure working gas in the hot-end cylinder 11 flows into the cold-end cylinder 12;

[0053] S2: After the high-temperature, high-pressure gas in the hot-end cylinder 11 flows into the cold-end cylinder 12, the working gas pressure in the hot-end cylinder 11 further decreases. Once it reaches the set value, the valve control mechanism 62 closes the valve 6, thereby closing the airflow path of the piston 4. The piston 4 continues to move toward the cold-end cylinder 12 due to its inertia (or external force, such as the inertia of a flywheel or engine rotor), compressing the working gas mixed with the high-temperature working gas in the cold-end cylinder 12.

[0054] S3: After the cold-end cylinder 12 receives the high-temperature working gas flowing into the hot-end cylinder 11, it mixes with the low-temperature working gas originally inside. After the mixing, the working gas heats up and expands, and the pressure increases. After the piston 4 moves to the cold dead point P2, it pushes the piston 4 in the reverse direction toward the hot-end cylinder 11;

[0055] S4: At the end of the expansion phase of the working gas in the cold-end cylinder 12, as the volume of the cold-end cylinder increases, the working gas pressure in the cylinder decreases. When the pressure reaches the set value, the valve control mechanism 62 opens the valve 6, opening the air flow path of the piston 4, and the high-pressure working gas in the cold-end cylinder 12 flows into the hot-end cylinder 11. The remaining working gas in the cold-end cylinder 12 continues to cool and contract under the cooling effect of the second heat exchanger 3.

[0056] S5: After the low-temperature working gas in the cold-end cylinder 12 flows into the hot-end cylinder 11, the working gas pressure in the cold-end cylinder 12 further decreases. When it decreases to a set value, the valve control mechanism 62 closes the valve 6, closing the airflow path of the piston 4. The piston 4 continues to move toward the hot-end cylinder 11 due to inertia (or other external forces, such as the inertia of the flywheel or engine rotor), compressing the working gas mixed with the low-temperature working gas in the hot-end cylinder 11.

[0057] S6: After the piston 4 moves to the hot dead point P1, the low-temperature mixed working gas in the hot end cylinder 11 is heated by the first heat exchanger 2, expands, and pushes the piston 4 to move in the reverse direction, repeating the cycle from S1 to S5.

[0058] This application can be used in working scenarios with ultra-low temperature cooling sources (such as liquid gas):

[0059] At the cooling end, the refrigeration equipment 31 uses an ultra-low temperature cold source (such as liquid air, etc.) to continuously cool the refrigerant (such as liquid propane). The refrigerant enters the second heat exchanger 3 inside the cold-end cylinder 12 through the second circulation pump 32 and the delivery pipeline. The gas medium in the cold-end cylinder 12 shrinks in volume and the pressure decreases due to the cooling. At this time, when the valve 6 is closed and the air flow channel is closed, the working gas in the hot-end cylinder 11 has a large pressure difference with the working gas in the cold-end cylinder 11, which will push the piston 4 to move and perform work externally; at the heating end, the heating equipment 21 uses seawater or high-temperature factory exhaust gas and other heating fluid heat media. The heat medium enters the first heat exchanger 2 inside the hot-end cylinder 11 through the first circulation pump 22 and the delivery pipeline. The first heat exchanger 2 will continuously heat the working gas in the hot-end cylinder 11. The working gas heats up and expands, pushing the piston 4 to perform work externally. When the piston 4 is running, the valve control mechanism is used to close or open the piston's air flow channel, thereby achieving gas expansion and work and the exchange of working gases at the cold and hot ends. According to the above-mentioned working process, the working principle of the Stirling engine is realized.

[0060] More preferably, because flowing water has excellent heat dissipation capabilities, this design can be applied to scenarios with water flow to achieve higher efficiency. The heating device 21 at the heating end uses fossil fuel to heat the fluid heat medium. The fluid heat medium enters the first heat exchanger 2 inside the hot end cylinder 11 through the first circulation pump 22 and the delivery pipeline. The first heat exchanger 2 continuously heats the working gas in the hot end cylinder 11. The working gas expands and increases in pressure due to the heat. When the valve 6 of the piston 4 is closed and the air flow channel is closed, it pushes the piston 4 to move and perform external work. At the cooling end, the cooling device 31 uses external flowing water to dissipate heat and cool the refrigerant. The refrigerant enters the second heat exchanger 3 inside the cold end cylinder 12 through the second circulation pump 32 and the delivery pipeline, continuously cooling the working gas in the cold end cylinder 12. The working gas is cooled and its pressure decreases, and its volume shrinks. When the piston 4 is running, the valve control mechanism 62 closes or opens the valve 6, closing or opening the air flow channel, to achieve gas expansion, work, and the exchange of the hot and cold gas media. According to the aforementioned workflow, the working principle of the Stirling engine is realized.

[0061] The beneficial effects of this program are analyzed as follows:

[0062] The present invention provides a new design in which cylinder hot and cold end heat exchangers serve as heat and cold sources, placed inside the cylinder to directly heat and cool the working gas within the cylinder. Compared to the Alpha-type Stirling engine, an external heat source directly heats the cylinder block. Due to the greater structural strength and low thermal conductivity of the cylinder block, this affects the engine's thermal power. Compared to the Beta-type Stirling engine, an external heat source directly heats the pipes connected to the cylinder. However, due to the lower strength of high-thermal-conductivity metal materials such as pipes at high temperatures, this becomes a shortcoming in the cylinder's strength and limits the maximum pressure of the gaseous working medium within the cylinder. In this design, the hot-end heat exchanger and the cold-end heat exchanger can withstand extremely high external working gas pressures, resulting in a simple cylinder structure, higher thermal power, and better pressure resistance.

[0063] Since both the hot medium and the cold medium are transported to the inside of the cylinder through pipes, the engine can be arranged away from the heat source and the cold source, which greatly facilitates the installation and use of the equipment and greatly expands the application scenarios of this design scheme.

[0064] The single piston, shaft, and rack-and-pinion mechanism replaces the existing crankshaft-connecting rod-flywheel mechanism, effectively simplifying the engine structure, reducing mechanical losses, improving mechanical efficiency, and significantly reducing installation space and equipment weight. While the preferred embodiments of the present invention have been described in detail above, it should be understood that after reading the above teachings of the present invention, those skilled in the art will be able to make various changes or modifications to the present invention. Such equivalents are also within the scope of the appended claims.

Claims

1. A single-cylinder internal heat type hot gas engine, characterized in that: include: Cylinder assembly, the cylinder comprising a hot end cylinder and a cold end cylinder, the hot end cylinder and the cold end cylinder are combined and docked to form a closed single cylinder and an insulation ring is provided between them; a first heat exchanger disposed in the hot end cylinder and in fluid communication with an external heat source for heating the working gas in the hot end cylinder; a second heat exchanger disposed in the cold-end cylinder and in fluid communication with an external cold source for cooling the working gas in the cold-end cylinder; a piston, the piston being a single piston, mounted in the cylinder assembly and capable of reciprocating linear motion within the cylinder, wherein the piston is provided with an air flow channel and a valve, the air flow channel being used to connect the working gas in the hot-end cylinder and the cold-end cylinder, and the valve being used to control the on / off of the air flow channel; as well as A piston rod, one end of which is connected to the piston, and the other end of which is connected to a transmission mechanism located outside the cylinder assembly.

2. The single-cylinder internal heat type hot gas engine according to claim 1, characterized in that: The valve includes a valve gate and a valve driving mechanism; The valve gate is provided with a through hole, and the piston is provided with an axial vent hole serving as the air flow channel; The valve gate and the valve driving mechanism are mounted on the piston. The valve driving mechanism is used to drive the valve gate to rotate so that the through hole and the axial vent hole are aligned or staggered, that is, the valve is opened or closed.

3. The single-cylinder internal heat type hot gas engine according to claim 2, characterized in that: The valve drive mechanism includes a control rack, a control gear and a pneumatic device, The control gear and the valve gate are coaxially fixedly mounted on the same shaft sleeve, and the shaft sleeve is rotatably mounted on the piston rod; The pneumatic device is mounted on the piston and connected to the control rack; The control rack is engaged with the control gear.

4. The single-cylinder internal heat type hot gas engine according to claim 1, characterized in that: The external heat source includes a heating device and a first circulation pump; the first heat exchanger, the first circulation pump and the heating device are connected through corresponding pipelines to form a heat medium circulation loop.

5. The single-cylinder internal heat type hot gas engine according to claim 1, characterized in that: The external cold source includes a refrigeration device and a second circulation pump; the second heat exchanger, the second circulation pump and the refrigeration device are connected through corresponding pipelines to form a cold medium circulation loop.

6. The single-cylinder internal heat type hot gas engine according to claim 1, characterized in that: One end of the cylinder assembly is provided with a through hole for the piston rod to pass through, and the through hole cooperates with the piston rod to seal the high-pressure working gas in the cylinder assembly.

7. The single-cylinder internal heat type hot gas engine according to claim 1, characterized in that: The transmission mechanism includes a transmission gear and a transmission rack. The transmission rack is fixedly connected to the piston rod, and the transmission gear is meshed with the transmission rack.

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